Gaza's Hamas strongman on Tuesday was quoted as challenging the Islamic militant movement's top leader because of his tacit backing of Palestinian negotiations with Israel.

The comments by Mahmoud Zahar were carried by the Lebanese newspaper al-Akhbar on Tuesday and signaled a rare public dispute among Hamas leaders. A Hamas statement in Gaza claimed the comments were fabricated, but did not explain.

Zahar was quoted as saying the group's exiled leader, Khaled Mashaal, had no right to say that Hamas would give Palestinian President Mahmoud Abbas another chance to try to negotiate a peace deal with Israel. Hamas and Abbas' Fatah movement recently reconciled after a four-year split, and Mashaal made those comments while sealing the deal.

"We didn't know and were not consulted about the position of Khaled Mashaal, and this is not the correct position," Zahar was quoted as telling the newspaper. "We haven't given any chance for negotiations on behalf of us or the Palestinian people. Our program is against negotiations in this way, because they are a waste of time."

In the newspaper interview, Zahar was also quoted as saying that Hamas' power structure should be reassessed. The movement's key leaders are based in the Syrian capital of Damascus.

Zahar suggested that the emphasis should shift to the Palestinian territories. "The leadership is here, and the part (of Hamas) that is abroad is just a part of that," the newspaper quoted him as saying. He said the current power structure has harmed the movement "and needs an assessment."

Izzat al-Risheq, a Mashaal confidant, said Zahar spoke out of turn.

"The statements of brother Mahmoud Zahar are wrong. They don't present the position of the movement and its institutions," al-Risheq said in a statement. "Brother Zahar does not have the mandate to comment on the speech of the head of the movement."

The apparent dispute comes at a sensitive time for Hamas. The Islamic militants and their hard-line ideology — they refuse to recognize Israel or renounce violence — are under renewed international scrutiny because of the reconciliation agreement with Abbas, a Western-backed moderate.

President Barack Obama has said Israel cannot be expected to negotiate with a movement that refuses to recognize its existence. Abbas has argued that he represents the Palestinians, and that a future Palestinian unity government would consist of nonpolitical professionals, not supporters of Hamas or Fatah.